@polianad22, I see you are learning more about multifocal and multicentric breast cancer, sometimes referred to as MMBC. Breast cancers are defined as multifocal when there is more than one distinct tumor within the same quadrant of the breast (MF) and multicentric when multiple cancers develop in different quadrants of the breast (MC).

Members @betsyk and @anne72 have mentioned having multifocal breast cancer and may be able to share their experiences with lymph node testing and spread.

I found this study that supports your understanding of lymph node spread and dissection options:
- Multiple synchronous (multifocal and multicentric) breast cancer: Clinical implications https://www.sciencedirect.com/science/article/abs/pii/S0960740410000587

Excerpt
"Multifocality in breast cancer is a frequent phenomenon, whose prevalence may vary between 13 and 75%. The differences in estimation of the prevalence of multifocality across studies may be explained by the differing definitions used for multifocality and multicentricity; this inconsistency makes it difficult to analyze the literature on the subject. The incidence of multifocality is probably often underestimated. Currently, the diagnosis relies on imaging. "
"Multifocality may also modify the management of the axillary basin; studies have shown that multifocality is associated to an over-risk of 20% of lymph node invasion."

It is likely that more members have multifocal and/or multicentric breast cancer.

Poliana, what are you learning about MMBC that is influencing your diagnostic and treatment options?